Glass is desirable for numerous properties and applications, including optical clarity and overall visual appearance. For some example applications, certain optical properties (e.g., light transmission, reflection and/or absorption) are desired to be optimized. For example, in certain example instances, reduction of transmission of UV (ultraviolet) radiation through glass may be desirable for storefront windows, IG window units, monolithic window units, display cases, and so forth.
Existing UV-blocking formulations based on silica may have extremely low viscosity, e.g., around 4 cp at 10 rpm. Such a low viscosity may be problematic when applying this coating by curtain coating method in which a substrate moves with a very high speed. The low viscosity may, for example, lead to a non-uniform coating thickness, problem in curing, cause of back splash, etc.
Accordingly, it will be appreciated that there is a need of a rheological modifier to enhance the viscosity of a UV-coating solution. Preferably, this modifier should be compatible with ingredients used in the UV-blocking formulations. Furthermore, the coating solution preferably behaves much like a Newtonian fluid after adding rheological modifier, preferably, e.g., at high revolutions per minute (rpm). A Newtonian fluid is a fluid that behaves similarly to water (in which the viscosity does not vary as a function of the force(s) acting upon the fluid, e.g., such as shear stress). A coating solution with high viscosity and Newtonian behavior may be desirable for at least several well-known coating processes, such as curtain coating, roller coating, dip coating, etc.
In certain aspects, this invention relates to use rheological modifier which not only compatible with the formulation but enhances the viscosity of UV-blocking coating solution. In an exemplary embodiment, the rheological modifier may be based on an acrylic latex.
In some aspects, this invention relates the enhancement in the viscosity of UV-coating solution at high shear rate or rpm. Furthermore, the Newtonian behavior at higher rpm of the UV-coating solution may be enhanced after the addition of rheological modifier.
Certain example embodiments of this invention relate, in part, to the formulation and manufacture of composition(s) containing a UV-blocking solution comprising a rheological modifier, which is preferably an acrylic latex.
These composition(s) may improve the rheological characteristics of a UV-blocking solution. These composition(s) may be used in a variety of applications, including, for example, UV-blocking coatings, optical coatings, functional coatings, and so forth. Such UV-blocking coatings may be used in applications such as for storefront windows, IG (insulating glass) window units, monolithic window units, display cases, and so forth.
Certain example embodiments relate to a method of making a rheologically enhanced ultraviolet-blocking coating solution. The method may include: forming a solution by mixing at least a polymeric silane, a solvent, acetone, acetic acid, and a rheological enhancer, wherein the rheological enhancer comprises an acrylic latex; and agitating the solution.
In certain example embodiments of this invention, there is provided a method of making a method of making a rheologically enhanced ultraviolet-blocking coating solution. The method may include: forming a solution by adding and stirring the following ingredients: a first solvent; acetone; an intermediate, wherein the intermediate was formed by serially mixing a first silane, a phenone, a triethlyamine, and a second solvent; a second silane; a color stock, wherein the color stock was formed by mixing a third solvent, acetone, a colorant, and a colloidal silica; acetic acid; water; and a rheological enhancer.
In certain example embodiments, there is provided a composition that may comprise a first solvent; acetone; an intermediate, wherein the intermediate comprises a first silane, a phenone, a triethlyamine, and a second solvent; a second silane; a color stock, wherein the color stock comprises a third solvent, acetone, a colorant, and a colloidal silica; acetic acid; water; and a rheological enhancer. The rheological enhancer may comprise an acrylic latex including high solids and a hydrophobically modified alkali-soluble emulsion. The composition may be used in making UV-blocking coatings.
In certain example embodiments, there is a coated article including a glass substrate; and an ultraviolet-blocking film provided on the glass substrate; wherein the film comprises a rheological enhancer for improving the rheological properties of a composition that forms a precursor to the film, wherein the rheological enhancer comprises an acrylic latex. The coated article may be a coated glass substrate used in an IG window unit, a monolithic window unit, a display case, and/or the like.